The purpose of the COMS (Collaborative Ocular Melanoma Study) is to determine the best treatment regimens for ocular melanoma, i.e. which treatment, if any, alters mortality and which, if any, (other than enucleation) might allow retention of some vision. Patients with large tumors are randomized to enucleation or to enucleation preceded by external radiation. Patients with medium sized tumors are randomized to enucleation or to brachytherapy with a 125I plaque.